We are having the following odd issue in our C# application that
automates Excel. We wrote a layer of code which creates the Excel
objects, handles them and then calls Marshal.ReleaseComObject on them
and setts them to null. We were very meticuluos to go through and
ensure nothing is being referenced without it being released. Here's
what's happening. The first iteration through, Excel opens exceutes
fine but hangs around after the call to GC.Collect. Because Excel isn't
going away on it's own, I kill Excel from the task manager here. On all
subsequent interations, Excel executes properly and dissapears after
each time on it's own. Does anyone have suggestions as to what's going
on? Why is Excel hanging around after the first iteration?
thanks!

Hi Matthew,

I have made a test, but I can not reproduce the problem. Below is my test
code, you may have a try and let me know the result.
for(int i=0;i<5;++i)
{
Excel.Application exapp = new Excel.ApplicationClass();
exapp.Quit();
Marshal.ReleaseComObject(exapp);
exapp = null;
GC.Collect();
}
Did I misunderstand your meaning?
You may try to use the late binding to automation the excel application.
e.g.
for(int i=0;i<5;++i)
{
Type t = Type.GetTypeFromProgID("Excel.Application");
object o =System.Activator.CreateInstance(t);
object r = t.InvokeMember("Quit",BindingFlags.InvokeMethod,nu ll,o,new
object[]{});
Marshal.ReleaseComObject(o);
o = null;
GC.Collect();
}

Can you post your code for me to reproduce the problem?


Regards,
Peter Huang
Microsoft Online Partner Support
Get Secure! www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no rights.

--------------------
Date: Tue, 02 Sep 2003 17:17:29 -0400
From: Matthew Wieder
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4)
Gecko/20030624 Netscape/7.1 (ax)
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Subject: Excel Automation Issue
Content-Type: text/plain; charset=us-ascii; format=flowed
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Newsgroups: microsoft.public.excel.programming
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Xref: cpmsftngxa06.phx.gbl microsoft.public.excel.programming:412281
X-Tomcat-NG: microsoft.public.excel.programming

We are having the following odd issue in our C# application that
automates Excel. We wrote a layer of code which creates the Excel
objects, handles them and then calls Marshal.ReleaseComObject on them
and setts them to null. We were very meticuluos to go through and
ensure nothing is being referenced without it being released. Here's
what's happening. The first iteration through, Excel opens exceutes
fine but hangs around after the call to GC.Collect. Because Excel isn't
going away on it's own, I kill Excel from the task manager here. On all
subsequent interations, Excel executes properly and dissapears after
each time on it's own. Does anyone have suggestions as to what's going
on? Why is Excel hanging around after the first iteration?
thanks!

The code is a few thousand lines, broken up into several classes so
posting it wouldn't be prudent. Basically, I am doing what you are
below (first code snippet) with doing a bunch more stuff with Excel each
time. After the first iteration, Excel stays around, but if I manually
kill it, all subsequent iterations take care of removing Excel
themselves. It's almost as if the memory is dirty somehow when I come
in and it takes an iteration through my code to clean all the handles so
everything functions properly afterward; how would I solve this?
thanks.

Peter Huang [MSFT] wrote:
Hi Matthew,

I have made a test, but I can not reproduce the problem. Below is my test
code, you may have a try and let me know the result.
for(int i=0;i<5;++i)
{
Excel.Application exapp = new Excel.ApplicationClass();
exapp.Quit();
Marshal.ReleaseComObject(exapp);
exapp = null;
GC.Collect();
}
Did I misunderstand your meaning?
You may try to use the late binding to automation the excel application.
e.g.
for(int i=0;i<5;++i)
{
Type t = Type.GetTypeFromProgID("Excel.Application");
object o =System.Activator.CreateInstance(t);
object r = t.InvokeMember("Quit",BindingFlags.InvokeMethod,nu ll,o,new
object[]{});
Marshal.ReleaseComObject(o);
o = null;
GC.Collect();
}

Can you post your code for me to reproduce the problem?


Regards,
Peter Huang
Microsoft Online Partner Support
Get Secure! www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no rights.

--------------------

Date: Tue, 02 Sep 2003 17:17:29 -0400
From: Matthew Wieder
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4)

Gecko/20030624 Netscape/7.1 (ax)

X-Accept-Language: en-us, en, he
MIME-Version: 1.0
Subject: Excel Automation Issue
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Message-ID:
Newsgroups: microsoft.public.excel.programming
NNTP-Posting-Host: 207.106.112.178
Lines: 1
Path: cpmsftngxa06.phx.gbl!TK2MSFTNGP08.phx.gbl!TK2MSFTN GP11.phx.gbl
Xref: cpmsftngxa06.phx.gbl microsoft.public.excel.programming:412281
X-Tomcat-NG: microsoft.public.excel.programming

We are having the following odd issue in our C# application that
automates Excel. We wrote a layer of code which creates the Excel
objects, handles them and then calls Marshal.ReleaseComObject on them
and setts them to null. We were very meticuluos to go through and
ensure nothing is being referenced without it being released. Here's
what's happening. The first iteration through, Excel opens exceutes
fine but hangs around after the call to GC.Collect. Because Excel isn't
going away on it's own, I kill Excel from the task manager here. On all
subsequent interations, Excel executes properly and dissapears after
each time on it's own. Does anyone have suggestions as to what's going
on? Why is Excel hanging around after the first iteration?
thanks!

Your code works fine, consistently.

Peter Huang [MSFT] wrote:

Hi Matthew,

I do not know if you has tested my code. So please perform the two
tests(late binding and early binding) I posted in last post.
I hope you can create a new console project to make the test. This will
help me narrow down and isolate the problem more quickly. I think this will
take you
some time, I appreciate your efforts.

It seems that you are making a great project which will concern many
objects. Since I can not reproduce the problem, so I hope you can make the
tests(both early binding and late binding in two independent project).


Regards,
Peter Huang
Microsoft Online Partner Support
Get Secure! www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no rights.

--------------------

Date: Wed, 03 Sep 2003 08:43:15 -0400
From: Matthew Wieder
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4)

Gecko/20030624 Netscape/7.1 (ax)

X-Accept-Language: en-us, en, he
MIME-Version: 1.0
Subject: Excel Automation Issue
References:



In-Reply-To:
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Message-ID:
Newsgroups: microsoft.public.excel.programming
NNTP-Posting-Host: 207.106.112.178
Lines: 1
Path: cpmsftngxa06.phx.gbl!TK2MSFTNGP08.phx.gbl!tk2msftn gp13.phx.gbl
Xref: cpmsftngxa06.phx.gbl microsoft.public.excel.programming:412439
X-Tomcat-NG: microsoft.public.excel.programming

The code is a few thousand lines, broken up into several classes so
posting it wouldn't be prudent. Basically, I am doing what you are
below (first code snippet) with doing a bunch more stuff with Excel each
time. After the first iteration, Excel stays around, but if I manually
kill it, all subsequent iterations take care of removing Excel
themselves. It's almost as if the memory is dirty somehow when I come
in and it takes an iteration through my code to clean all the handles so
everything functions properly afterward; how would I solve this?
thanks.

Peter Huang [MSFT] wrote:

Hi Matthew,

I have made a test, but I can not reproduce the problem. Below is my

test

code, you may have a try and let me know the result.
for(int i=0;i<5;++i)
{
Excel.Application exapp = new Excel.ApplicationClass();
exapp.Quit();
Marshal.ReleaseComObject(exapp);
exapp = null;
GC.Collect();
}
Did I misunderstand your meaning?
You may try to use the late binding to automation the excel application.
e.g.
for(int i=0;i<5;++i)
{
Type t = Type.GetTypeFromProgID("Excel.Application");
object o =System.Activator.CreateInstance(t);
object r = t.InvokeMember("Quit",BindingFlags.InvokeMethod,nu ll,o,new
object[]{});
Marshal.ReleaseComObject(o);
o = null;
GC.Collect();
}

Can you post your code for me to reproduce the problem?


Regards,
Peter Huang
Microsoft Online Partner Support
Get Secure! www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no

rights.

--------------------


Date: Tue, 02 Sep 2003 17:17:29 -0400
From: Matthew Wieder
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4)

Gecko/20030624 Netscape/7.1 (ax)


X-Accept-Language: en-us, en, he
MIME-Version: 1.0
Subject: Excel Automation Issue
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Message-ID:
Newsgroups: microsoft.public.excel.programming
NNTP-Posting-Host: 207.106.112.178
Lines: 1
Path: cpmsftngxa06.phx.gbl!TK2MSFTNGP08.phx.gbl!TK2MSFTN GP11.phx.gbl
Xref: cpmsftngxa06.phx.gbl microsoft.public.excel.programming:412281
X-Tomcat-NG: microsoft.public.excel.programming

We are having the following odd issue in our C# application that
automates Excel. We wrote a layer of code which creates the Excel
objects, handles them and then calls Marshal.ReleaseComObject on them
and setts them to null. We were very meticuluos to go through and
ensure nothing is being referenced without it being released. Here's
what's happening. The first iteration through, Excel opens exceutes
fine but hangs around after the call to GC.Collect. Because Excel isn't
going away on it's own, I kill Excel from the task manager here. On all
subsequent interations, Excel executes properly and dissapears after
each time on it's own. Does anyone have suggestions as to what's going
on? Why is Excel hanging around after the first iteration?
thanks!

Hi Matthew,

Since I can not review your code, I can not figure out what is the problem
exactly. I just have a guess based on my experience that the problem may
usually be caused by that there are references have not been released.
So I suggest you check if there are references that have not been released.
To narrow down the large project, you may check them by simplifying your
code step by step.

Did you have any related question, please feel free to let me know.


Regards,
Peter Huang
Microsoft Online Partner Support
Get Secure! www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no rights.
--------------------
Date: Fri, 05 Sep 2003 11:23:36 -0400
From: Matthew Wieder
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4)
Gecko/20030624 Netscape/7.1 (ax)
X-Accept-Language: en-us, en, he
MIME-Version: 1.0
Subject: Excel Automation Issue
References:





In-Reply-To:
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Message-ID:
Newsgroups: microsoft.public.excel.programming
NNTP-Posting-Host: 207.106.112.178
Lines: 1
Path: cpmsftngxa06.phx.gbl!TK2MSFTNGP08.phx.gbl!tk2msftn gp13.phx.gbl
Xref: cpmsftngxa06.phx.gbl microsoft.public.excel.programming:413137
X-Tomcat-NG: microsoft.public.excel.programming

I'm using C# and can't make unqualified method calls, so that's not the
issue. I'll go through my code more carefully to make sure everything
is being released, but even if I missed releasing something, why would
Excel only stick around after the first iteration and not the others?
thanks!

Peter Huang [MSFT] wrote:
Hi Matthew,

Since my demo code works well on your machine, then you may check if
your
code makes an unqualified method call or property call to an Office
object.
Here is a KB link.
http://support.microsoft.com/?id=319832

To narrow down the problem, I hope you can try to simplified your code
step
by step.

Regards,
Peter Huang
Microsoft Online Partner Support
Get Secure! www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no
rights.
--------------------

Date: Thu, 04 Sep 2003 09:22:44 -0400
From: Matthew Wieder
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4)

Gecko/20030624 Netscape/7.1 (ax)

X-Accept-Language: en-us, en, he
MIME-Version: 1.0
Subject: Excel Automation Issue
References:





In-Reply-To:
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Message-ID:
Newsgroups: microsoft.public.excel.programming
NNTP-Posting-Host: 207.106.112.178
Lines: 1
Path: cpmsftngxa06.phx.gbl!TK2MSFTNGP08.phx.gbl!tk2msftn gp13.phx.gbl
Xref: cpmsftngxa06.phx.gbl microsoft.public.excel.programming:412743
X-Tomcat-NG: microsoft.public.excel.programming

Your code works fine, consistently.

Peter Huang [MSFT] wrote:


Hi Matthew,

I do not know if you has tested my code. So please perform the two
tests(late binding and early binding) I posted in last post.
I hope you can create a new console project to make the test. This will
help me narrow down and isolate the problem more quickly. I think this

will

take you
some time, I appreciate your efforts.

It seems that you are making a great project which will concern many
objects. Since I can not reproduce the problem, so I hope you can make

the

tests(both early binding and late binding in two independent project).


Regards,
Peter Huang
Microsoft Online Partner Support
Get Secure! www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no

rights.

--------------------


Date: Wed, 03 Sep 2003 08:43:15 -0400
From: Matthew Wieder
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4)

Gecko/20030624 Netscape/7.1 (ax)


X-Accept-Language: en-us, en, he
MIME-Version: 1.0
Subject: Excel Automation Issue
References:



In-Reply-To:
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Message-ID:
Newsgroups: microsoft.public.excel.programming
NNTP-Posting-Host: 207.106.112.178
Lines: 1
Path: cpmsftngxa06.phx.gbl!TK2MSFTNGP08.phx.gbl!tk2msftn gp13.phx.gbl
Xref: cpmsftngxa06.phx.gbl microsoft.public.excel.programming:412439
X-Tomcat-NG: microsoft.public.excel.programming

The code is a few thousand lines, broken up into several classes so
posting it wouldn't be prudent. Basically, I am doing what you are
below (first code snippet) with doing a bunch more stuff with Excel
each
time. After the first iteration, Excel stays around, but if I
manually
kill it, all subsequent iterations take care of removing Excel
themselves. It's almost as if the memory is dirty somehow when I come
in and it takes an iteration through my code to clean all the handles
so
everything functions properly afterward; how would I solve this?
thanks.

Peter Huang [MSFT] wrote:


Hi Matthew,

I have made a test, but I can not reproduce the problem. Below is my

test


code, you may have a try and let me know the result.
for(int i=0;i<5;++i)
{
Excel.Application exapp = new Excel.ApplicationClass();
exapp.Quit();
Marshal.ReleaseComObject(exapp);
exapp = null;
GC.Collect();
}
Did I misunderstand your meaning?
You may try to use the late binding to automation the excel
application.
e.g.
for(int i=0;i<5;++i)
{
Type t = Type.GetTypeFromProgID("Excel.Application");
object o =System.Activator.CreateInstance(t);
object r =

t.InvokeMember("Quit",BindingFlags.InvokeMethod,nu ll,o,new

object[]{});
Marshal.ReleaseComObject(o);
o = null;
GC.Collect();
}

Can you post your code for me to reproduce the problem?


Regards,
Peter Huang
Microsoft Online Partner Support
Get Secure! www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no

rights.


--------------------



Date: Tue, 02 Sep 2003 17:17:29 -0400
From: Matthew Wieder
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4)

Gecko/20030624 Netscape/7.1 (ax)



X-Accept-Language: en-us, en, he
MIME-Version: 1.0
Subject: Excel Automation Issue
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Message-ID:
Newsgroups: microsoft.public.excel.programming
NNTP-Posting-Host: 207.106.112.178
Lines: 1
Path: cpmsftngxa06.phx.gbl!TK2MSFTNGP08.phx.gbl!TK2MSFTN GP11.phx.gbl
Xref: cpmsftngxa06.phx.gbl microsoft.public.excel.programming:412281
X-Tomcat-NG: microsoft.public.excel.programming

We are having the following odd issue in our C# application that
automates Excel. We wrote a layer of code which creates the Excel
objects, handles them and then calls Marshal.ReleaseComObject on
them
and setts them to null. We were very meticuluos to go through and
ensure nothing is being referenced without it being released.
Here's
what's happening. The first iteration through, Excel opens exceutes
fine but hangs around after the call to GC.Collect. Because Excel

isn't

going away on it's own, I kill Excel from the task manager here. On

all

subsequent interations, Excel executes properly and dissapears after
each time on it's own. Does anyone have suggestions as to what's

going

on? Why is Excel hanging around after the first iteration?
thanks!